I just had some REV 10s installed with the double brackets on my vlx on a G3, from the pics it looks like they will definitely interfere with the Z5 mounts. Not that it cant be modified by the installer.
One thing on the Z5, I had a Z5 with one of my boats for a couple seasons, they hold gear which is really nice but there were some definite con's to having them. First, I could not walk under it without ducking everytime or I would hit my head on it (I am 6'1"). You cant ever take it down on the water quickly, if you do, its a contraption to put it back up and you have a skeleton frame showing. They are difficult to store, and a wind sail when towing. And they are very expensive, $3k on a G3 I heard???
Some folks are now installing surf pockets on there bimini, which is so much cheaper and allows you to stow surfboards and collapse the bimini when you want open sun in the boat. The G3 also allows the quad board racks to hold extra gear. I know Samson is making some nice swivel surf racks for the G3 for probably half the cost of the Z5.
Just something to consider...